The World Health Organisation (WHO) has declared the outbreak a global health emergency, with Zika now spreading "explosively" in Latin America.

In response to the situation, American Holidays and Travelmood are permitting pregnant customers concerned about travel to affected countries to change their bookings, Independent.ie Travel has learned.

Customers must provide a doctor's note to confirm their pregnancy, with changes to travel dates possible up to October 31, under certain conditions.

Falcon Holidays and Thomson, set to begin direct charters to Mexico this June, are also offering pregnant customers booked to travel to the Zika-affected country the opportunity to amend their itineraries without a fee.

Another operator, Tropical Sky, is looking at holidays on a case-by-case basis.

"Where possible we will cancel or amend holidays without any cancellation or amendment fees," says its Sales Director, Brian Sargent.

"We've asked our members to pull out all the stops," says Pat Dawson, President of the Irish Travel Agents' Association (ITAA).

"However, the gift of changing is in the airline and bed providers' hands. Every booking is treated differently... but I would hope that providers would act in the common good of the couple in such a situation."

Zika is a disease transmitted by Aedes mosquitoes, similar to Dengue Fever, with flu-like symptoms including fever, rash and joint pain.

There are concerns that infection during pregnancy may be linked with microcephaly, a foetal abnormality in babies, although a direct link has not been confirmed.

The pandemic has thrust long-haul and honeymoon destinations like Mexico and the Dominican Republic into the spotlight, with the Department of Foreign Affairs changing its travel advice for 32 countries and territories in recent days.

Minister of Foreign Affairs, Charlie Flanagan, said:

"While the risk is low in most cases, I would particularly urge pregnant women and women who are trying to become pregnant to consider postponing their travel to affected areas and to consult with their healthcare provider before travel.”

Case-by-case confusion

The Department has stopped short of declaring travel to be unsafe, however, so travel insurers or tour operators are not obliged to offer refunds or changes.

Going to press, British Airways is offering pregnant customers due to fly to affected areas the option of refunds or amended journeys within the next month.

Lufthansa, United, American Airlines, JetBlue and Delta are also offering refunds.

Royal Caribbean, the biggest cruise company in terms of Irish sales, is providing alternative itinerary options to pregnant women "who do not feel comfortable sailing to countries affected with the Zika virus", it said.

There is no treatment or cure for Zika, with travellers advised to take precautionary measures to avoid being bitten by mosquitoes in affected areas.

UPDATE: On February 3, Sunway said it will review holidays on a case by case basis, "and will do our utmost to assist clients who wish to cancel or amend holidays where possible without cancellation or amendment fees."